Engine coolant deaeration system



June 14, 1966 J. w. WALSH ENGINE COOLANT DEAERATION SYSTEM Filed Sept.18, 1964 ldflwwwwwww INVENTOR. 19/211 (1/ Milk/1 7 OzQ/Vi'y UnitedStates Patent 3,255,740 ENGINE CODLANT DEAERATION SYSTEM John W. Walsh,Lockport, N.Y., assignor to General Motors Corporation, Detroit,-Mich.,a corporation of Delaware Filed Sept. 18, 1964, Ser. No. 397,525 Claims.(Cl. 123-4109) This invention relates to engine cooling systems and moreparticularly to systems for cooling internal combustion engines by meansof a circulatory liquid.

Internal combustion engines and particularly diesel engines aresusceptible to the entry of combustion gases into the cooling systemscausing the water or coolant pumps to become air locked. The entrainmentof air or combustion gases in a coolant in other ways detracts from thedesired efficiency of a given engine cooling system and it is obviousthat an improved efiective and simple way for removing gases from enginecoolants is desirable while retaining control of engine temperatures.The difliculty is much more serious with diesel engines as distinguishedfrom other engines. The attempted solution in that case has been thecustomary one neve1thelessto add bleed holes in the thermostat but thisexpediency causes loss of coolant temperature control so that radiatorshutters are needed to keep coolant leakage flowing in the radiator frombecoming too cold under certain ambient conditions. Under low ambienttemperature conditions, the conventional cooling systems tend toover-cool engines causing a loss in the latters efiiciency.

An object of the present invention is to provide an engine coolantdeaeration system in which one tank of a radiator is enabled to serve asa deaeration tank as engine temperature control is automaticallymaintained under a wide range of ambient temperature conditions and withavoidance of any carefully sized or balanced deaeration lines orbafiles. v

To this end a feature of the present invention is an engine coolantdeaeration system in which one tank of a radiator at all times serves toprovide a zone for the removal of air or gases from a coolant regardlessof Whether or not the radiator core is bypassed by a thermostatic valve.

This and other important features of the invention will now be describedin detail in the specification and then pointed out more particularly inthe appended claims.

In the drawings:

FIGURE 1 is a diagramatic view, in perspective, of a portion of a V-8engine jacket associated with a radiator heater, a two-way thermostaticvalve, an oil cooler and a Water pump;

FIGURE 2 is an enlarged sectional view looking in the direction of thearrows 22 through the thermostatic valve of FIGURE 1;

FIGURE 3 is a view similar to that of FIGURE 2 but with a main valve anda bypass valve each partially opened; and

FIGURE 4 is a view similar to that of FIGURES 2 and 3 but with the mainvalve fully opened and the bypass valve closed.

The portion of a V-8 engine jacket is shown in FIGURE 1 as associatedwith a conventional radiator 12 which comprises a top or deaeration tank14 and a bottom or second tank 16. The tank 14 is provided with aconventional filler neck 18 having a pressure cap 20 and a vent line 22.A suitable filler neck and pressure cap is disclosed in the UnitedStates Patent 3,047,235 granted July 31, 1962 in the name of I. Eshbaughand I. Mc- Dougal. A themostat valve 24 is shown at the junction ofthree conduits 26, 28, and and this valve is also connected by thelatter to the inlet side of an air cooler 32. The coolant outlet side ofthe latter is connected by means of an elbow 34 to the coolant pump 36.The discharge side of the pump 36 is connected to the engine jacket 10.A heater core 40 for heating the passenger compartment of the vehicle isconnected to the engine jacket 10 by a conduit 42 and to the inlet sideof the pump by a conduit 44. This heater core or the oil cooler 32 formsno part of the present invention but each is shown in a preferredarrangement with the particular embodiment of the cooling systemillustrated. The dis charge of the jacket 10 is connected by a conduit46 to the deaeration or upper tank 14 of the radiator 12.

The thermostatic valve 24 comprises two casing parts 50 and 52 betweenwhich is interposed a gasket 54. This gasket surrounds an insertedannular valve seat 56 which is tightly held in the part 52 of the valveand a spider portion of which slidingly holds a plunger of a main valve58. The latter is movable to closed and opened positions with relationto the annular seat member 56 and a pellet motor casing 59 is firmlyheld in fixed relation to the seat member by means not shown. The casingpart 50 of the valve 24 defines an annular inlet chamber 60 connected byradial passages 62 to a central passage 64 and the latter is inalignment with the main valve 58. The annular chamber 60 is connected toa neck 70 which in turn is adapted to be connected by a suitablecoupling to one end of the conduit 28. The upstream side of the mainvalve 58 is connected by a neck 72 to the conduit 26 leading from thebottom tank 16. Further details regarding the valve 24 are not givenhere as they form no part of the present invention. It sufiices to say,however, that heat opens the main valve 58 and closes a bypass orsecondary valve 73 controlling the passages 62. A suitable thermostaticvalve is disclosed in the United States Patent 2,899,026, Hitch et al.or in United States Patent 2,988,068, Waydak.

When the main valve 58 of the thermostat 24 is atfull closed position,as shown in FIGURE 2, the total coolant flow is from the radiator toptank 14 and through the conduit 28 to the annular chamber 60 and then byWay of radial ports 62 to the chamber 64 and the line 30 back to theengine jacket. As the main valve is closed, there is no flow of coolantthrough the radiator core and although at this time the engine is cold,any gases forming in the coolant are promptly deaerated from the uppertank 14 by way of the pressure cap 20 and the vent 22. The tank 14provides adequate opportunity for entrained gas to separate and bafflesare not necessary.

As the engine becomes warm and the thermostat 24 operates to control theengine temperature, the main valve 58 partially opens and the bypassvalve 73 partially closes as shown in FIGURE 3. A controlled engine orsystem temperature then exists wherein some coolant flowsthrough theradiator core and the remainder flows through bypass line 28 withdeaeration being effected in the tank 14 from the complete flow.

When the bypass valve 73 is fully closed as shown in FIGURE 4, the mainvalve 58 Will be fully opened and all the coolant flows through theradiator core and the conduit 26 giving the maximum cooling efiect.Under this heated engine condition as during the controlled flowcondition, the top tank 14 is effective to remove any entrapped gasesfrom the coolant with no supplementary tanks being needed.

It should be noted that the bypass conduit 28 is preferably connected asloW as possible to the top tank 14 and at a distance from the connectionof the conduit 46. This separation of the points of joinder of conduits46 and 28 to the top tank 14 permits adequate separation of the gas fromthe coolant. The fittings for the heater core 40 are located in lowerplaces in the system where small coolant flow turbulence occurs.

I claim:

1. An engine coolant deaeration system comprising an engine jacket, aradiator with a top tank and a bottom tank, a pump, atwo-waythermostatic valve, first conduit means connecting said bottom tank tosaid valve, pump and jacket in series and in that order, second conduitmeans connecting said jacket, top tank and valve in series and in thatorder, the points of joinder of said second conduit means to said toptank being spaced to facilitate separation of gas, and the valve beingsuch as to make said first conduit means effective when said jacket isheated and to make said second conduit means effective when said jacketis not heated.

2. An engine coolant deaeration system comprising an engine jacket, aradiator with a deaeration tank connected to a second tank by a core, apump, a two-way thermostatic valve, first conduit means connecting saidtank to said valve, pump and jacket in series and in that order,

second conduit means connecting said jacket, deaeration tank and valvein series and in that order, and the valve being such as to effect flowthrough the radiator and said first conduit means when said jacket isheated and to elfect flow through the second conduit means around saidcore to said pump when said jacket is not heated.

3. An engine coolant deaeration system comprising an engine jacket, aradiator with a deaeration tank connected to a second tank by a core, apump, a two-way thermostatic valve, a vent on said deaeration tank,first conduit means cooperating in connecting said second tank to oneway of said valve, said pump and said jacket in series,

second conduit means cooperating in connecting said jacket, deaerationtank and the other way of said valve in series, and the system beingsuch that any fiow under any condition in said system is through saiddeaeration tank.

4. An engine coolant deaeration system comprising an engine jacket, aradiator with an upper tank and a lower tank connected by a core, apump, a two-way thermostatic valve, a vent on said upper tank, firstconduit means cooperating in connecting said lower tank to one way ofsaid valve, said pump and said jacket in series, second conduit meanscooperating in connecting said jacket, upper tank and the other way ofsaid valve in series, and. the arrangement being such that all fiowthrough said thermostatic valve is from said upper tank.

5. An engine coolant deaeration system as set forth in claim 4, saidthermostatic valve including a main valve controlling the fiow throughsaid core and a bypass valve controlling the flow around said core tosaid pump.

References Cited by the Examiner UNITED STATES PATENTS 1,311,809 8/1919Giesler 23634.5 2,296,641 9/1942 Hawkins l2341.1 2,332,680 10/1943Wallace 12341.54 X 2,336,068 12/1943 Charles 12341.1 2,988,068 6/1961Waydale 12341.1 3,014,467 12/1961 Middendorf l2341.1

KARL J. ALBRECHT, Primary Examiner.

1. AN ENGINE COOLANT DEAERATION SYSTEM COMPRISING AN ENGINE JACKET, ARADIATOR WITH A TOP TANK AND A BOTTOM TANK, A PUMP, A TWO-WAYTHERMOSTATIC VALVE, FIRST CONDUIT MEANS CONNECTING SAID BOTTOM TANK TOSAID VALVE, PUMP AND JACKET IN SERIES AND IN THAT ORDER, SECOND CONDUITMEANS CONNECTING SAID JACKET, TOP TANK AND VALVE IN SERIES AND IN THATORDER, THE POINTS OF JOINDER OF SAID SECOND CONDUIT MEANS TO SAID TOPTANK BEING SPACED TO FACILITATE SEPARATION OF GAS, AND THE VALVE BEINGSUCH AS TO MAKE SAID FIRST CONDUIT MEANS EFFECTIVE WHEN SAID JACKET ISHEATED AND TO MAKE SAID SECOND CONDUIT MEANS EFFECTIVE WHEN SAID JACKETIS NOT HEATED.